package com.hmdp.service.impl;

import cn.hutool.core.bean.BeanUtil;
import cn.hutool.core.bean.copier.CopyOptions;
import cn.hutool.core.util.RandomUtil;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.hmdp.dto.LoginFormDTO;
import com.hmdp.dto.Result;
import com.hmdp.dto.UserDTO;
import com.hmdp.entity.User;
import com.hmdp.mapper.UserMapper;
import com.hmdp.service.IUserService;
import com.hmdp.utils.RegexUtils;
import com.hmdp.utils.UserHolder;
import lombok.extern.slf4j.Slf4j;
import org.springframework.data.redis.connection.BitFieldSubCommands;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Service;

import javax.annotation.Resource;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;
import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.UUID;
import java.util.concurrent.TimeUnit;

import static com.hmdp.utils.RedisConstants.*;
import static com.hmdp.utils.SystemConstants.USER_NICK_NAME_PREFIX;

/**
 * <p>
 * 服务实现类
 * </p>
 *
 * @author 虎哥
 * @since 2021-12-22
 */
@Slf4j
@Service
public class UserServiceImpl extends ServiceImpl<UserMapper, User> implements IUserService {
    @Resource
    StringRedisTemplate stringRedisTemplate;

    @Override
    public Result login(LoginFormDTO loginForm, HttpSession session){
        // 校验手机号
        String phone = loginForm.getPhone();
        if(RegexUtils.isPhoneInvalid(phone)){
            return Result.fail("手机号格式不正确");
        }


        String code = loginForm.getCode();
        String password = loginForm.getPassword();
        User user = query().eq("phone", phone).one();
        // 从redis中获取验证码并校验
        // 优先校验验证码
        if (code != null && code.length() == 6){
            String cacheCode = stringRedisTemplate.opsForValue().get(LOGIN_CODE_KEY + phone);
            if(cacheCode == null || !cacheCode.equals(code)){
                return Result.fail("验证码错误");
            }
        }else{
            // 校验密码
            if(user != null && password != null){
                user = query().eq("phone", phone).eq("password", password).one();
                if(user == null){
                    return Result.fail("用户名或密码错误");
                }
            }
            if(user != null){
                user.setPassword(password);
            }
        }

        // 判断用户是否存在
        if(user == null){
            // 不存在，则创建
            user = createUserWithPhone(phone);
        }

        // 保存用户信息到session
        // 生成随机token作为令牌
        String token = UUID.randomUUID().toString();
        // 将User对象转存到HashMap
        UserDTO userDTO = BeanUtil.copyProperties(user, UserDTO.class);
        Map<String,Object> userMap = BeanUtil.beanToMap(userDTO, new HashMap<>(),
                CopyOptions.create()
                        .setIgnoreNullValue(true)
                        .setFieldValueEditor((fieldName,fieldValue) -> fieldValue.toString()));
        // 存储
        String tokenKey = LOGIN_USER_KEY + token;
        stringRedisTemplate.opsForHash().putAll(tokenKey, userMap);
        // 设置token有效期
        stringRedisTemplate.expire(tokenKey, LOGIN_USER_TTL, TimeUnit.MINUTES);

        return Result.ok(token);
    }

    @Override
    public Result sendCode(String phone, HttpSession session) {
        // 校验手机号
        if(RegexUtils.isPhoneInvalid(phone)){
            return Result.fail("手机号格式不正确");
        }
        // 生成验证码,保存到session然后发送
        String code = RandomUtil.randomNumbers(6);
        // 保存验证码到redis而不是session
        stringRedisTemplate.opsForValue().set(LOGIN_CODE_KEY + phone, code, LOGIN_CODE_TTL, TimeUnit.MINUTES);
        log.debug("发送验证码：{}，{}", phone, code);
        return Result.ok();
    }

    @Override
    public Result logout(HttpServletRequest request) {
        String token = request.getHeader("authorization");
        stringRedisTemplate.delete(LOGIN_USER_KEY + token);
        return Result.ok("用户已退出");
    }

    @Override
    public Result sign() {
        // 获取当前用户以及日期
        Long userId = UserHolder.getUser().getId();
        LocalDateTime now = LocalDateTime.now();
        // 准备key
        String keySuffix = now.format(DateTimeFormatter.ofPattern(":yyyyMM"));
        String key = USER_SIGN_KEY + userId + keySuffix;
        // 获取今天是本月第几天
        int dayOfMonth = now.getDayOfMonth();
        // 写入redis, SET key offset 1
        stringRedisTemplate.opsForValue().setBit(key, dayOfMonth-1, true);
        return Result.ok();
    }

    @Override
    public Result signCount() {
        // 获取当前用户
        Long userId = UserHolder.getUser().getId();
        LocalDateTime now = LocalDateTime.now();
        // 准备key
        String keySuffix = now.format(DateTimeFormatter.ofPattern(":yyyyMM"));
        String key = USER_SIGN_KEY + userId + keySuffix;
        int dayOfMonth = now.getDayOfMonth();
        List<Long> result = stringRedisTemplate.opsForValue().bitField(
                key,
                BitFieldSubCommands.create()
                        .get(BitFieldSubCommands.BitFieldType.unsigned(dayOfMonth))
                        .valueAt(0)
        );

        if (result == null || result.isEmpty()){
            // 没有结果
            return Result.ok(0);
        }
        Long num = result.get(0);
        if(num == null){
            return Result.ok(0);
        }
        // 循环遍历
        int count = 0;
        while (true){
            if ((num & 1) == 0){
                break;
            }else{
                count++;
            }
            // 右移并抛弃末位
            num >>>= 1;
        }
        return Result.ok(count);
    }

    private User createUserWithPhone(String phone) {
        User user = new User();
        user.setPhone(phone);
        // 默认用户名 user 前缀 + 随机字符串
        user.setNickName(USER_NICK_NAME_PREFIX + RandomUtil.randomString(6));
        // 保存用户
        save(user);
        return user;
    }
}
